The Regent wrote:
Personally, I found her character grating over time. I didn't understand her choosing Garak over her father after all he'd done and gave up for her. She just kept on betraying him the moment she felt a little angry then it was right back to him because she couldn't stay mad.
All he did was not kill her. That's it. If it wasn't for Kira, Dukat would have killed Ziyal. She really doesn't owe Dukat anything. And her choosing Garak over Dukat isn't betrayal, it's just her making her own decisions without having to get relationship approval from her father(that shit went out of style 400 years ago).